GB865371A - Tire supporting apparatus - Google Patents

Abstract

865,371. Tyre supporting apparatus. SMYSER, J. A. May 15, 1958 [May 21, 1957], No. 15626/58. Class 144 (1). An apparatus for supporting a tubeless tyre to be worked on, such as by buffing, comprises an expansible rim 50 of arcuate channel-section segments 51 sleeved by a rubber ring 70 which covers each segment channel base 52 between the channel side flanges 63 and resiliently urges the segments to contracted positions circumferentially abutting each other coaxial with a support shaft 21, the segments being supported on the shaft 21 by means for moving the segments radially outwardly to expand the band 70 into sealing engagement with the beads of the tyre, and the band having an inflating valve 75-77 for inflation of the tyre to force the tyre beads against the segment side flanges 63. 'As shown the shaft 21 carrying a rotatable sleeve 25 is supported on a frame 20 to extend adjustably adjacent the work-machine. The sleeve 25 is oppositely screw-threaded at its ends to engage correspondingly threaded collars 35, and carries a hand wheel 92 at its free end. Each segment 51 is radially guided by a rod 45 slidable in a tubular spoke 43 radiating from a hub 40 axially located on the sleeve 25. Additionally each segment is pivotally connected to the collars 35 by a pair of rigid links 59 so that on rotation of the sleeve 25 by the hand wheel 92, the collars 35 are oppositely displaced to move the segments radially inwardly or outwardly to contracted or expanded positions. To prevent pinching of the band 70 and to hold the band circular in expanded position, resiliently flexible steel plates 80 are bonded to the inner periphery of the band to bridge the gaps between the segments. In use the tyre is readily seated on the segments in their contracted position. In an alternative arrangement for expanding the segments, the hub 40 and rods 45 are omitted, one collar 35 is anchored to the sleeve 25, which is unthreaded, and the other collar 35 is slidable towards the anchored collar by an hydraulic piston coaxially surrounding the sleeve 25, retraction of the movable collar being effected on release of the hydraulic pressure by the resilience of the band 70.